The secret, then, is to know the moveset. Start with a team of Rayquazas. If Hitmonchan has ice punch, then bail, restart the raid, and switch to the team of Moltreses. Or use whatever it takes to take it down. Gardevoir vs. Close Combat, Golem vs. Fire Punch or Thunder Punch, Psychic Slowbro vs. Ice Punch, could also be effective.
GamePress
Hitmonchan analysis
"Those expecting an easy time with Hitmonchan are in for a surprise. With his abysmal HP mitigated by tier 3’s constant 3000 HP, Hitmonchan becomes very bulky. He doesn’t hit very hard, although his non-legendary counters don’t like being hit to begin with. Overall, a fairly challenging boss, especially for those lacking in Mewtwo."
The problem of hitmonchan isn't as simple as frail non-legendary counters. If it only has fighting moves it would be a bit easier because his attack is mediocre.
It's basically that its counters literally almost never resist its common attacks, as it only has 1 fighting fast move out of 4 moves. Its attacks are also very spammable and can wipe out pokemon by themselves, and Rayquaza is stopped by Ice Punch and Moltres is stopped by Thunder Punch.
So add that nearly none of its counters resists its attacks, and its common attacks are all spammable punch moves?
Report
Answers
You can tell with the autoselect. Don't use that team but you CAN predict the moves with the autoselect, and in this case you cannot completely phase Alakazam, Espeon, Mewtwo and Gardevoir. The only thing you can do is to not use Moltres when thunderpunch and not use Rayquaza when Ice Punch.
Most of Hitmonchan's counters don't resist anything from him but counter and close combat by the way, which is the point of this post and what makes it actually troublesome in addition to he has a tendency to aggressively spam those moves. Hitmonchan itself has little ability to harm Alakazam or Espeon in alarming speeds because its attack is mediocre, especially with close combat.
He isnt easy. I beat him durring fighting event and it went down to the last seconds. A lot of people will underestimate him cuz they still dont understand that def is the stat that matters and there Hitmonchan is pretty solid for an otherwise weak Pokemon.
However, the auto select should reveal his charged move so it should be clear when to use Moltres or Rayquaza/ Hurricane Nite.
Also keep in mind that because his shit attack stats Alakazam & Espeon can actually take a punch for once.
It's not that complicated. It is simply a race against time. If I've said it once, I've said it a hundred times: DON'T DODGE in these time-sensitive solo raids. For Hitmonchan, what you need are four or five high-DPS glass cannons (C/FS Alakazams or Espeons), and one or two tanks (Lugia) at the end to ensure survivablity. Hurricane Dragonites, flying Rayquazas, C/P or C/SB Mewtwos are helpful if you have them.
Summary: Confusion is your friend, and don't dodge.
Thing is, it's not simply a race against time if you don't have Lugia or you brought in Dragonite and Ray against Ice Punch. That's what makes Hitmonchan a much more interesting raid than Onix or Claydol and why unique lineups against it can be real nail-biters.
Dodging also sometimes improves your DPS. Death animations take time and dying with a half full charge bar takes a lot of time. Dodging is the main tool to ensure that your mon dies at the right moment to maximize its DPS.
